Since 2012, the PFA has provided a dedicated service to help with its members' well-being, and the numbers taking advantage of that are on the rise.

"We put a player welfare department in place in 2012 because I felt a lot of onus was being placed on the physical aspect of players playing football and not enough on their emotional side, and I think the two go hand-in-hand,'' PFA head of welfare Michael Bennett told PA Sport.

"Last year we had 160; of which 62 were current players and 98 were former players, and that is growing year on year.

"Key for me is making our members aware of what is in place and the more we raise awareness, the more people will use the service.

"I think it is a male mindset that it is seen as a weakness so for people like Clarke Carlisle, Rio Ferdinand -- even Prince Harry -- to talk about their own experience brings the taboo down and you become more comfortable being able to talk about it.

"We are trying to change that mindset because if you were to twist an ankle or pull a hamstring -- because you can physically see it -- you can treat it, but because mental illness is something you can't see it is not viewed the same as something you can see.''

Aaron Lennon is not alone in dealing with a mental health issue, according to the PFA. Martin Rickett/PA Wire

The PFA has put in place a system which offers a variety of help and advice options, ranging from a 24-hour phone line to access to a psychiatrist.

PFA chief executive Gordon Taylor told Sky Sports News: "Mental health is something which can affect a significant number of the population for different reasons -- and sport is not immune from that.''

Taylor cited the benefit of the professional federations of different sports coming together to deal with issues, adding: "This is a common ground for us all. The helpline has been seen to be very, very helpful.''

Former PFA chairman Carlisle, who had a season at Leeds with Lennon early in his career, has suffered from mental health issues himself and attempted suicide in 2014.

He believes it should not come as a surprise when such an issue affects a professional footballer.

"People are still surprised because they believe to have a mental health illness needs to be justified by circumstance,'' he told Liverpool's Radio City Talk. "Mental health issues are as indiscriminate as any other illness.

"In Aaron's case I am saddened as he is a former colleague and a friend of mine, but I am not shocked at all because statistics tell me he is in the prime bracket to be affected by this not only by age but also by social demographic: a young, black man in the modern era is highly susceptible to certain mental health issues.

"I know Everton are one of the leading clubs when it comes to care and welfare in the community and their club so I have no doubt whatsoever Aaron and his family will get the full support of the club.''